Biomedical subjects

B Zeschmar-Lahl

Publications and source records attributed to B Zeschmar-Lahl.

3 recordsLinked to original sources

PubMed1995

[Air microbial burden at garbage sorting facilities].

At two german garbage sorting facilities, germ concentrations in the air were analyzed at different working environments (waste reception, manual sorting). At plant A, maximum concentrations of total bacteria (14700 CFU/m3), gram-negative bacteria (7279 CFU/m3) and moulds (> 84806 CFU/m3) occurred in the air at the final manual sorting belts. Referring to concentrations of total bacteria and moulds, concentrations in the air at the final sorting belts were significantly higher (p < 0.001) than at the other working environments. At plant B, the counts of total bacteria reached 7173 CFU/m3 in the air at the waste reception site and 5512 CFU/m3 at the manual sorting belt. Maximum concentrations for gram-negative bacteria were 247 resp. 206 CFU/m3 and 70919 resp. 60848 CFU/m3 for moulds. At the waste reception site, the aerial concentrations of total bacteria lay highly significantly (p < 0.001) and of moulds significantly (p < 0.05) above aerial concentrations at the manual sorting belt. As causes, an intensive mechanical pretreatment of recycle material at plant A and whirling up of sedimentary dust of the floor during manual sweeping of the material on to the transportation at plant B are discussed.

Air Microbiology↗

PubMed1994

[Composting facilities. 2. Aerogenic microorganism content at different working areas of composting facilities].

At two composting facilities (plants D and E), contamination of the air with total bacteria and mould fungi, and in addition with gram-negative bacteria (only at plant D) was analyzed at different indoor sites and outdoor in the vicinity. Statistical validity of the determination of contents of microorganisms in air samples was guaranteed by the collection and analysis of 30 parallel samples. At plant D, total bacteria concentrations in outdoor air ranged from 106 to 15,618 CFU/m3 air (median: 495 CFU/m3 air), gram-negative bacteria concentrations ranged up to 71 CFU/m3 air (median: below the detection limit of 35 CFU/m3 air), and mould fungi reached 7,138 CFU/m3 air (median: 141 CFU/m3 air). Highest concentrations of total bacteria above the upper detection limit (> 84,806 CFU/m3 air, sample volume: 28.3 l) and of mould fungi (38,940 CFU/m3 air) occurred at the place where three months old compost was mixed, highest concentrations of gram-negative bacteria (14,134 CFU/m3 air) were measured during mixing of fresh compost (younger than 8 days). Maximum and median values of the examined microorganisms ranged so high that special protective means for personnel working directly beneath the mixing process seem to be necessary under hygienic aspects. Raw and clean air at the composting filter at plant D showed highly significant differences concerning air concentration of gram-negative bacteria and mould fungi, indicating a good separation efficiency for these types of microorganisms. Maximum and median values of gram-negative bacteria and mould fungi concentrations (all < 1,000 CFU/m3 air) measured in clean air behind the composting filter lie in the range of normal outdoor air. Merely total bacteria show statistical significant differences to outdoor air with median values of clean air of 1,979 CFU/m3 air (edge of filter) resp. 3,110 CFU/m3 air (upside the filter) and with maximum values of above 30,000 CFU/m3 air in each case. In the outdoor air at plant E, total bacteria concentrations ranged from 362 to 7,633 CFU/m3 air (median: 1,312 CFU/m3 air), mould fungi ranged from 115 to 4,072 CFU/m3 air (median: 345 CFU/m3 air). Highest concentrations of total bacteria and mould fungi (all analyses above the upper detection limit of 21,201 CFU/m3 air; sample volume: 113,2 l) occurred during shredding of a mixture of kitchen and green wastes and of shrubs. During experimental shredding of separately collected panty diapers air concentrations of total bacteria ranged from about 19,000 CFU/m3 air to > 21,201 CFU/m3 air.(ABSTRACT TRUNCATED AT 400 WORDS)

Air Microbiology↗

PubMed1994

[Composting facilities. 1. Microbiological quality of compost with special regard to disposable diapers].

At three different composting facilities, co-composting of used panty diapers with an addition of 10% (weight) to the usual plant input was investigated for various hygienic and microbiological parameters. In nearly any case, a sufficient degree of germ reduction above 99.9% could be observed by determination of reduction rates of B. subtilis spores. The concentrations of "total microorganisms" ranged from 3.9 x 10(5) to 3.3 x 10(11) colony forming units per gram compost (CFU/g) in composts without and from 3.3 x 10(5) to 4.7 x 10(9) CFU/g in composts with panty diapers in the input. The concentrations of "gram-negative bacteria" ranged from 3.3 x 10(4) to 1.3 x 10(9) CFU/g (without panty diapers) resp. from 3.3 x 10(5) to 3.5 x 10(8) CFU/g (with panty diapers), the concentrations of "fecal streptococci" from 1.7 x 10(3) to 7.7 x 10(7) CFU/g (without panty diapers) resp. from 1.4 x 10(4) to 1.4 x 10(8) CFU/g (with panty diapers). Facultatively pathogenic microorganisms showed a broad variety, but no common trend in composts with and without panty diapers in the input. Statistical validity of the determination of contents of microorganisms in compost samples was guaranteed by the collection and analysis of 20 parallel samples with an average sample mass of 10 to 15 kg. From the analyzed quantitative and qualitative hygienic-microbiological parameters, it can be concluded that no negative hygienic-microbiological effects, caused by the addition of 10% (weight) of used panty diapers in the input, have to be expected. Under the aspects of epidemiologic hygiene, composting of used panty diapers together with usual input materials seems to cause no increased risks under the tested conditions. Under the aspect of consumer protection, there is no increase in the risk of infection when using compost produced with addition of panty diapers, compared to compost produced without panty diaper addition to the input.

Bacillus subtilis↗